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Volume 40, Issue 9
Displaying 1-8 of 8 articles from this issue
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Juji YOSHIMURA1982 Volume 40 Issue 9 Pages 778-795
Published: September 01, 1982
Released on J-STAGE: November 13, 2009
JOURNAL FREE ACCESSAdvances in the syntheses of branched-chain sugars during the last decade were reviewed. Over forty kinds of naturally occurring branched-chain sugars are classified into two types ; i. e. one having no substituent at the branching point and another having a substituent such as hydroxyl, amino, nitro groups, and various synthetic methods for synthesis of both types from different intermediates were introduced.View full abstractDownload PDF (2210K) -
Haruhiko AOYAGI, Nobuo IZUMIYA1982 Volume 40 Issue 9 Pages 796-805
Published: September 01, 1982
Released on J-STAGE: January 22, 2010
JOURNAL FREE ACCESSRecent synthetic aspects of three cyclic peptides are reviewed. On the syntheses of gramicidin S, an antibacterial cyclodecapeptide, and its analogs, several methods for cyclization were performed using various deca- and pentapeptide precursors. Among them, the succinimide active ester and azide methods gave desired products in good yield. Furthermore, the yield of the products was found to depend highly on amino acid sequence of the precursors. Five analogs of Cyl-2, a phytotoxic cyclotetrapeptide, were synthesized. Comparison of Cyl-2 with the analogs by NMR implied that Cyl-2 has an unique conformation. AM-toxin I, II and III are phytotoxic cyclotetradepsipeptides containing dehydroalanine. The proposed structures of the toxins could be synthetically confirmed by different methods. Conversion of serine residue in cyclotetradepsipeptide precursors to dehydroalanine via β-elimination was unsatisfactory, whereas reasonable improvement was obtained by using Hofmann degradation of α, β-diaminopropionic acid.View full abstractDownload PDF (1240K) -
Shigeo TAZUKE1982 Volume 40 Issue 9 Pages 806-823
Published: September 01, 1982
Released on J-STAGE: November 13, 2009
JOURNAL FREE ACCESSIn view of the recent importance of photoresponsive polymers such as photoresist, photochromic polymer, photoconductive polymer, polymeric photosensitizer and many others, an attempt of molecular designing was described. The principle is based on the assumption that any specific molecular function stems from molecular interactions so that the first step should be to understand the polymer structure-molecular interactions in the ground and excited state-unctionality correlation. Specificity of polymer systems in excimer and exciplex formation, and energy migration was studied in relation to the polymer structure, the degree of polymerization, and the environment effects with the aid of over 30 new polymers and their model compounds. The information was then applied to design photopolymers containing anthracene unit which behaved as either photocrosslinkable or photochromic polymers. Photoconductive polymers containing trans-1, 2-bis (9-carbazolyl) cyclobutane units were also designed and synthesized. The excellent performance was demonstrated. Fluorescence spectroscopy showed that the polymers satisfied the conditions to be good photoconductors.View full abstractDownload PDF (1856K) -
Yoshiaki INAMOTO1982 Volume 40 Issue 9 Pages 824-838
Published: September 01, 1982
Released on J-STAGE: January 22, 2010
JOURNAL FREE ACCESSA review is made for the recent findings on biological activities (antimicrobial, plant-hormonal, herbicidal, insecticidal, pheromone, medicinal, and toxicological) of natural as well as synthetic aliphatic bridged and condensed polycyclic compounds (alkaloids, steroids, prostaglandins, adamantane and heteroadamantane compounds, and dicyclopentadiene derivatives being excluded). Polycyclic skeletons so far used are mainly bicyclic norborn (en) yl, isobornyl, bicyclo [2. 2. 2] octyl, bicyclo [3. 3. 1] nonyl and their oxygen and nitrogen analogs, and more complex tri- and polycyclic ones are found less utilities, probably because of the difficulties involved in their acquisitions. In the field of medicine synthesis, most of the efforts are devoted to modify the established drugs with polycyclic residues in the hope of enhancement of the activities with the high lipophilicity and reluctant decomposition delivered by these three-dimensional, densely packed, bulky skeletons, rather than to discover new polycyclic structures with unexpected pharmacological actions. The latter purpose seems to have been achieved mostly by the physiological studies of natural products which, also hereafter, would remain to be one of the most fruitful methodology for this objective.View full abstractDownload PDF (1612K) -
Tomijiro SATO, Masao YOKOTE1982 Volume 40 Issue 9 Pages 839-843
Published: September 01, 1982
Released on J-STAGE: November 13, 2009
JOURNAL FREE ACCESSPhenalenone derivatives are valuable compounds for dyes or their intermediates. Recently a number of papers and patents have been reported on syntheses of the phenalenones. This article deals with the synthetic methods of phenalenone skeletons available in the literature reported since 1964.View full abstractDownload PDF (542K) -
A Novel Reagent for Deoxygenative Condensation with Aromatic Carbonyl, Nitroso, and Nitro CompoundsMasao OKUBO1982 Volume 40 Issue 9 Pages 844-850
Published: September 01, 1982
Released on J-STAGE: November 13, 2009
JOURNAL FREE ACCESSAryliminodimagnesium (ArN (MgBr) 2, aryl-IDMg), derived from arylamines and two molar equivalents of ethylmagnesium bromide, condense with diaryl ketones, nitrosoarenes, and nitroarenes to give the corresponding anils, azoarenes, and azoxyarenes. Types of products and their distributions obtained in the reaction with benzophenones, fluorenones, benzalacetophenones, anthraquinone, and benzils showed that the aryl-IDMg reagents are moderately reactive in terms of electron-transfer as well as condensation ability. The condensation reaction of the reagents with nitroarenes provides a novel method for the independent preparation of isomeric pairs of unsymmetrically substituted azoxyarenes. The isolated azoxyarenes are deoxygenated to give the corresponding azoarenes by the treatment with an excess amount of the reagent. The product distributions obtained in the reaction of nitroarenes with excess reagents are governed mainly by the electronic effect of the substituent on both the substrate and the reagent.View full abstractDownload PDF (783K) -
Katsumi INOUE1982 Volume 40 Issue 9 Pages 851-852
Published: September 01, 1982
Released on J-STAGE: November 13, 2009
JOURNAL FREE ACCESSDownload PDF (205K) -
Hiroshi NISHINO1982 Volume 40 Issue 9 Pages 853-854
Published: September 01, 1982
Released on J-STAGE: November 13, 2009
JOURNAL FREE ACCESSDownload PDF (210K)
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